. It is not uncommon as one of the forms of hemorrhage in purpnra and scurvy ; it occurs as black vomit in yellow fever ; it sometimes follows the ingestion of some irritant poison. All of these are purely symptomatic, and their diagnosis is based, not on the mere existence of htematemesis, which is casual, but upon the other symptoms of each form of disease.
c. A certain admixture of blood with the contents of the stomach in per sistent vomiting is an early and only too certain indication of commencing scirrhus ; after ceasing for a time, it is very apt to reappear as ulceration proceeds. Its distinctive characters are a grumous and scarcely clotted appearance, much resembling " coffee grounds," and its small amount on each occasion, even when ulceration has proceeded to its greatest extent. This is to be explained by the circumstance that previous disorganization has generally rendered the vessels impervious before they are perforated by the ulcerative process.
§ 4. Iliematuria is the name given to any escape of blood with the urine. The presence of blood must not be assumed from its e,olor: some vegetable coloring matters give to the urine a pink or bright red hue; in some disorders, deposits of a red color closely resemble it; and an admixture of bile produces an ap pearance very similar to that caused by dark and altered blood. The details of this subject will be given afterwards (see Chap. XXX., § 3); but, as a ready test, it will be observed that, when blood is present, the urine is not only changed in color, but has lost its natural transparency, and this opacity is increased by heat and nitric acid. When the microscope can be employed, blood-globules will be seen, and give certainty to the diagnosis. In females it is further necessary to ascertain that the blood does not e,ome from the uterus or vagina at the time of mieturition.
Its source may be in any part of the urinary apparatus, from the minute tube,s of the kidney to the extremity of the urethra: in quantity and color it varies very much. When the amount is considerable and the color florid, it probably proceeds from some abrasion of surface, caused either (a) by the presence of a calculus, or (b) by ulceration or other injury, or it is the result of fungoid growth; (c) similar discharges occur in purpura and the hemorrhagic diathesis: (d) when in smaller amount, and of a pink, brown, or smoke color, it is generally a symptom of chronic dise,ase of the kidney.
a. Calculus.—Genemlly occurring in middle life, or in advanced age, the concretion may have lain quiescent in the kidney for a long period, until some sudden shock or movement causes its displacement, when its sharp edges wound the delicate membrane of the infundibulum, and give rise to a pretty copious flow of blood. This varies remarkably from day to day, till at length the membrane becomes adapted to the new position of the stone, or it passes out of the body. The blood has a tendency to coagulate, and small clots are seen at different times in the urine ; they are sometimes partially decolorized, having the shape of the ureter, and appearing like small white worms. The passage of the stone along the ureter is generally attended by symptoms very analopus to those indicating its presence in the kidney. Pain is always pre sent; it is situated in the region of the kidney, confined to one side, extending along the course of the ureter, and shooting down the groin and the thigh. with retraction of the testicle. The circumstances connected with this event will have to be more fully discussed when we speak of diseases of the kidney, under the head of Nephritis and Nephralgia. (Chap. XXXI., 1.) When the calculus is situated in the bladder, or has passed into the urethra. before it can become the cause of hemorrhage, there will be other symptoms of its presence ; mucous or purulent secretion, sudden stoppage in the urine, and pain referred to the glans penis, &c.
b. In disease of the bladder the largest amount of pare blood is passed, not nafreciaently almost unmixed with urine, coagulating into a solid mass in the utensil, or even entirely tilling the bladder with a firm clot. The disease is generally of a fungoid nature, but occasionally a similar amount of hemor rhage is prodaced by chronic ulceration ; in the latter, the previous history ought to indicate its cause ; in the former, the introduction of the catheter is attended with deep-seated pain and a flow of blood from the fungous surface. Fungoid disease of the kidney is also sometimes attended with pretty copious discharge of blood, but there is little to point out its true nature.